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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Generic electric propulsion drive : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand

Edmondson, Michael Charles January 2008 (has links)
Considerable resources worldwide are invested in the research and development of future transportation technology. The foreseen direction and therefore research of future personalised transportation is focused on Battery Electric Vehicles (BEV) or hybrid combinations that use hydrogen fuel cells. These new transport energy systems are consider most to replace the current vehicles powered by the internal combustion engine (ICE). The research work presented in this thesis mainly focuses on the development of a software control system for future BEV prototype vehicles - a generic intelligent control system (GICS). The system design adopts a modular design concept and intelligent control. The whole system consists of four modules being communication, power supply, motor driver and transmission module. Each module uses a microcontroller as the brain and builds an embedded control system within the module. The control and communication between the modules is based on a group of specific parameters and the status of a state machine. In order to effectively implement intelligent control and simplify the system structure and programming, a generic intelligent fuzzy logic model that can be configured to a specific application with a near real-time buffered communication methodology is developed. The tests made on the fuzzy control model and the near real-time buffered communication gave a very positive outcome. The implementation of the fuzzy control and the communication methodology in each of the modules results in a communication between the modules with a steady speed, better reliability and system stability. These modules link together through the communication channels and form a multi-agent collaborative system (MACS). As the controllers are designed based on the parametric concept, the system is able to be implemented to future new modules and therefore allow prototype vehicle control systems to be developed more efficiently. The MACS is based on the core components of the control system - fuzzy logic controller (FLC), Serial Communication and Analogue input control software modules. Further work is carried out as an attempt to integrate the control software with a hardware design for a generic electric propulsion drive (GEPD). This thesis therefore outlines the design and considerations in software and hardware integration in addition to the GICS. The output from this thesis being the construction of soft programming modules for embedded microcontroller based control system has been accepted and presented at two international conferences; one in Wellington, New Zealand[1] the second in Acireale, Italy[2].
212

Generic electric propulsion drive : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand

Edmondson, Michael Charles January 2008 (has links)
Considerable resources worldwide are invested in the research and development of future transportation technology. The foreseen direction and therefore research of future personalised transportation is focused on Battery Electric Vehicles (BEV) or hybrid combinations that use hydrogen fuel cells. These new transport energy systems are consider most to replace the current vehicles powered by the internal combustion engine (ICE). The research work presented in this thesis mainly focuses on the development of a software control system for future BEV prototype vehicles - a generic intelligent control system (GICS). The system design adopts a modular design concept and intelligent control. The whole system consists of four modules being communication, power supply, motor driver and transmission module. Each module uses a microcontroller as the brain and builds an embedded control system within the module. The control and communication between the modules is based on a group of specific parameters and the status of a state machine. In order to effectively implement intelligent control and simplify the system structure and programming, a generic intelligent fuzzy logic model that can be configured to a specific application with a near real-time buffered communication methodology is developed. The tests made on the fuzzy control model and the near real-time buffered communication gave a very positive outcome. The implementation of the fuzzy control and the communication methodology in each of the modules results in a communication between the modules with a steady speed, better reliability and system stability. These modules link together through the communication channels and form a multi-agent collaborative system (MACS). As the controllers are designed based on the parametric concept, the system is able to be implemented to future new modules and therefore allow prototype vehicle control systems to be developed more efficiently. The MACS is based on the core components of the control system - fuzzy logic controller (FLC), Serial Communication and Analogue input control software modules. Further work is carried out as an attempt to integrate the control software with a hardware design for a generic electric propulsion drive (GEPD). This thesis therefore outlines the design and considerations in software and hardware integration in addition to the GICS. The output from this thesis being the construction of soft programming modules for embedded microcontroller based control system has been accepted and presented at two international conferences; one in Wellington, New Zealand[1] the second in Acireale, Italy[2].
213

Generic electric propulsion drive : a thesis in the partial fulfilment of the requirements for the degree of Masters of Engineering in Mechatronics at Massey University, Turitea Campus, Palmerston North, New Zealand

Edmondson, Michael Charles January 2008 (has links)
Considerable resources worldwide are invested in the research and development of future transportation technology. The foreseen direction and therefore research of future personalised transportation is focused on Battery Electric Vehicles (BEV) or hybrid combinations that use hydrogen fuel cells. These new transport energy systems are consider most to replace the current vehicles powered by the internal combustion engine (ICE). The research work presented in this thesis mainly focuses on the development of a software control system for future BEV prototype vehicles - a generic intelligent control system (GICS). The system design adopts a modular design concept and intelligent control. The whole system consists of four modules being communication, power supply, motor driver and transmission module. Each module uses a microcontroller as the brain and builds an embedded control system within the module. The control and communication between the modules is based on a group of specific parameters and the status of a state machine. In order to effectively implement intelligent control and simplify the system structure and programming, a generic intelligent fuzzy logic model that can be configured to a specific application with a near real-time buffered communication methodology is developed. The tests made on the fuzzy control model and the near real-time buffered communication gave a very positive outcome. The implementation of the fuzzy control and the communication methodology in each of the modules results in a communication between the modules with a steady speed, better reliability and system stability. These modules link together through the communication channels and form a multi-agent collaborative system (MACS). As the controllers are designed based on the parametric concept, the system is able to be implemented to future new modules and therefore allow prototype vehicle control systems to be developed more efficiently. The MACS is based on the core components of the control system - fuzzy logic controller (FLC), Serial Communication and Analogue input control software modules. Further work is carried out as an attempt to integrate the control software with a hardware design for a generic electric propulsion drive (GEPD). This thesis therefore outlines the design and considerations in software and hardware integration in addition to the GICS. The output from this thesis being the construction of soft programming modules for embedded microcontroller based control system has been accepted and presented at two international conferences; one in Wellington, New Zealand[1] the second in Acireale, Italy[2].
214

Design Methodology for Modifying an Existing Internal Combustion Engine to Generate Power from a Stored Air System

January 2011 (has links)
abstract: A low cost expander, combustor device that takes compressed air, adds thermal energy and then expands the gas to drive an electrical generator is to be designed by modifying an existing reciprocating spark ignition engine. The engine used is the 6.5 hp Briggs and Stratton series 122600 engine. Compressed air that is stored in a tank at a particular pressure will be introduced during the compression stage of the engine cycle to reduce pump work. In the modified design the intake and exhaust valve timings are modified to achieve this process. The time required to fill the combustion chamber with compressed air to the storage pressure immediately before spark and the state of the air with respect to crank angle is modeled numerically using a crank step energy and mass balance model. The results are used to complete the engine cycle analysis based on air standard assumptions and air to fuel ratio of 15 for gasoline. It is found that at the baseline storage conditions (280 psi, 70OF) the modified engine does not meet the imposed constraints of staying below the maximum pressure of the unmodified engine. A new storage pressure of 235 psi is recommended. This only provides a 7.7% increase in thermal efficiency for the same work output. The modification of this engine for this low efficiency gain is not recommended. / Dissertation/Thesis / M.S. Mechanical Engineering 2011
215

Smart Car Technologies: A Comprehensive Study of the State of the Art with Analysis and Trends

January 2015 (has links)
abstract: Driving is already a complex task that demands a varying level of cognitive and physical load. With the advancement in technology, the car has become a place for media consumption, a communications center and an interconnected workplace. The number of features in a car has also increased. As a result, the user interaction inside the car has become overcrowded and more complex. This has increased the amount of distraction while driving and has also increased the number of accidents due to distracted driving. This thesis focuses on the critical analysis of today’s in-car environment covering two main aspects, Multi Modal Interaction (MMI), and Advanced Driver Assistance Systems (ADAS), to minimize the distraction. It also provides deep market research on future trends in the smart car technology. After careful analysis, it was observed that an infotainment screen cluttered with lots of small icons, a center stack with a plethora of small buttons and a poor Voice Recognition (VR) results in high cognitive load, and these are the reasons for the increased driver distraction. Though the VR has become a standard technology, the current state of technology is focused on features oriented design and a sales driven approach. Most of the automotive manufacturers are focusing on making the VR better but attaining perfection in VR is not the answer as there are inherent challenges and limitations in respect to the in-car environment and cognitive load. Accordingly, the research proposed a novel in-car interaction design solution: Multi-Modal Interaction (MMI). The MMI is a new term when used in the context of vehicles, but it is widely used in human-human interaction. The approach offers a non-intrusive alternative to the driver to interact with the features in the car. With the focus on user-centered design, the MMI and ADAS can potentially help to reduce the distraction. To support the discussion, an experiment was conducted to benchmark a minimalist UI design. An engineering based method was used to test and measure distraction of four different UIs with varying numbers of icons and screen sizes. Lastly, in order to compete with the market, the basic features that are provided by all the other competitors cannot be eliminated, but the hard work can be done to improve the HCaI and to make driving safer. / Dissertation/Thesis / Date collected about reaction time in the experiment_Excel / Masters Thesis Computer Science 2015
216

Look-Ahead Information Based Optimization Strategy for Hybrid Electric Vehicles

January 2016 (has links)
abstract: The environmental impact of the fossil fuels has increased tremendously in the last decade. This impact is one of the most contributing factors of global warming. This research aims to reduce the amount of fuel consumed by vehicles through optimizing the control scheme for the future route information. Taking advantage of more degrees of freedom available within PHEV, HEV, and FCHEV “energy management” allows more margin to maximize efficiency in the propulsion systems. The application focuses on reducing the energy consumption in vehicles by acquiring information about the road grade. Road elevations are obtained by use of Geographic Information System (GIS) maps to optimize the controller. The optimization is then reflected on the powertrain of the vehicle.The approach uses a Model Predictive Control (MPC) algorithm that allows the energy management strategy to leverage road grade to prepare the vehicle for minimizing energy consumption during an uphill and potential energy harvesting during a downhill. The control algorithm will predict future energy/power requirements of the vehicle and optimize the performance by instructing the power split between the internal combustion engine (ICE) and the electric-drive system. Allowing for more efficient operation and higher performance of the PHEV, and HEV. Implementation of different strategies, such as MPC and Dynamic Programming (DP), is considered for optimizing energy management systems. These strategies are utilized to have a low processing time. This approach allows the optimization to be integrated with ADAS applications, using current technology for implementable real time applications. The Thesis presents multiple control strategies designed, implemented, and tested using real-world road elevation data from three different routes. Initial simulation based results show significant energy savings. The savings range between 11.84% and 25.5% for both Rule Based (RB) and DP strategies on the real world tested routes. Future work will take advantage of vehicle connectivity and ADAS systems to utilize Vehicle to Vehicle (V2V), Vehicle to Infrastructure (V2I), traffic information, and sensor fusion to further optimize the PHEV and HEV toward more energy efficient operation. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2016
217

Modelo de referência para implantação de novos processos de montagem no setor automotivo. / Reference model for the implementation of new assembly processes in the automotive sector.

Emilio Carlos Baraldi 23 August 2017 (has links)
Existem muitos estudos e publicações focadas no planejamento e desenvolvimento de novos produtos. Porém, o mesmo não é notado em estudos relativos à implantação destes novos produtos e seus processos na área de manufatura. Para tal, é desenvolvido neste trabalho um modelo de referência consistente para a implantação de novos processos de montagem no setor automotivo. O citado modelo contém a descrição das etapas, as verificações de qualidade, as ações e as necessárias validações do produto produzido no processo de produção em série. O teste da consistência e relevância dessa metodologia ocorre por meio da aplicação do modelo proposto, no desenvolvimento de um processo da montagem de componentes na montagem final. Para a sua avaliação, compararam-se os indicadores de um processo existente em dois momentos: um primeiro, com o processo desenvolvido utilizando-se o método tradicional, e em segundo, com o desenvolvimento e implantação deste mesmo processo, utilizando-se o método proposto de desenvolvimento do processo produtivo, somado a uma avaliação qualitativa do modelo de referência, por meio de uma pesquisa, com especialistas reconhecidos do meio automotivo, validando-se assim o modelo proposto. / Currently, there are many studies and publications focused on the planning and development of new products. However, the same is not noted in studies related to the implementation of these new products and their processes in manufacturing area. For this, a consistent reference model is developed for implementation of new assembly processes in the automotive sector. This model contains a description of steps, quality checks, actions and validations required by the product manufactured in the serial production process. The test of consistency and relevance of this methodology occurs through the application of the proposed model, in the development of a process of component assembly in the final assembly. For its evaluation, the indicators of an existing process were compared in two time points: with the process developed using the traditional method, and secondly, with the development and implementation of this same process, using the proposed development method of the production process. This occurred alongside a qualitative evaluation of the reference model through a survey with recognized experts of the automotive environment, thus validating the proposed model.
218

Estudo da influência dos dutos de admissão no escoamento de ar em cabeçotes de motores de ignição por compressão utilizando simulações em CFD. / Study of the influence of intake ports on the air flow through cylinder heads of CI enginers using CFD simulations.

Marcel Amaro e Andrade de Morais Souza e Silva 17 October 2016 (has links)
O controle de emissões em veículos pesados está em foco desde a década de 90, com a criação de regulamentações nacionais e internacionais que impõe limites cada vez mais rígidos para as concentrações de poluentes emitidos por estes veículos. O desenvolvimento de novas tecnologias possui papel fundamental neste processo, buscando redução nos níveis de emissões com mínimo impacto negativo no desempenho e no consumo do veículo. Para tanto, o presente trabalho visa avaliar a influência da posição dos dutos de admissão de ar de cabeçotes de motores a combustão interna, especificamente em motores de ignição por compressão (MIC) de 4 válvulas, no escoamento de ar dentro do cilindro. O escoamento do ar e o movimento de swirl são fatores importantes para a mistura e distribuição do combustível injetado, e quando otimizados para uma queima melhor distribuída, contribuem para redução nos níveis de emissões. Procura-se investigar quais direções características dos dutos são determinantes para o escoamento e para o comportamento de swirl do motor através de simulações em fluidodinâmica computacional (Computational Fluid Dynamics - CFD) utilizando o programa CD-adapco STAR-CCM+®. Os resultados de alguns dos cenários simulados são comparados a resultados de testes experimentais realizados em bancada de medição de swirl, no âmbito de outro trabalho sendo desenvolvido no mesmo grupo de projeto. / The emissions control in heavy-duty vehicles has been in focus since the 1990\'s, with the creation of national and international regulations which impose strict limits for pollutant concentrations released by these vehicles. The development of new technologies has a fundamental role in this process, aiming the reduction of emission levels with minimum impact on the performance and fuel consumption of the vehicle. Therefore, the present study aims to evaluate the influence of the position of intake ports in cylinder heads from internal combustion engines, specifically 4-valves compression-ignition (CI) engines, in the in-cylinder air flow. The air flow and swirl motion are important factors for the mixture and distribution of injected fuel, and when optimized for a better distributed combustion, contribute for the reduction of emission levels. This study investigates the characteristic directions of ports which are determinant for the air flow and swirl behaviour of the engine through Computational Fluid Dynamics (CFD) simulations using CD-adapco software STAR-CCM+®. The results from a group of simulated cases are compared to experimental test results from another project, developed on the same project group, performed in a swirl meter test rig.
219

Critérios para seleção da arquitetura elétrica veicular em mercados emergentes. / Criteria for selection of vehicle electrical architectures for emerging markets.

Gustavo Dal Poggetto 03 July 2009 (has links)
Este estudo tem por objetivo estabelecer os principais critérios de seleção de uma arquitetura elétrica adequada a mercados emergentes, considerando as necessidades de mercado, de legislação, de inovações e/ou novas funções a serem empregadas durante o ciclo de vida de um veículo. Para tanto, o resultado da pesquisa bibliográfica deste trabalho, apresentada na revisão teórica, primeiramente define o significado de arquitetura elétrica, e conta a sua evolução desde os primórdios da indústria automotiva até os dias de hoje, apontando quais são os principais sistemas elétricos existentes atualmente, deixando clara a fundamental importância da eletrônica embarcada na evolução do automóvel. Mostram, ainda, suas principais tendências tecnológicas, além de um descritivo sobre técnicas, critérios e metodologia de desenvolvimento de projetos de arquitetura elétrica empregados hoje na indústria. Na seqüência, o trabalho define os conceitos de mercado emergente e mercado desenvolvido, apontando suas particularidades, volumes de negócio (histórico e projetado), deixando evidente a importância dos mercados emergentes nos dias de hoje para a indústria automotiva mundial e a necessidade de se estabelecer estratégias específicas para estes mercados. Com base na própria pesquisa bibliográfica, somada à análise documental e a entrevistas não-estruturadas com membros ativos da indústria automotiva, foram concebidos os critérios para seleção de arquiteturas elétricas veiculares para mercados emergentes, assim como seus descritores e taxas de substituição (pesos). A definição de pesos e descritores é necessária para a utilização do método de agregação aditiva, método este de tomada de decisão empregado devido a sua capacidade de avaliar simultaneamente diversas alternativas, através de parâmetros qualitativos. Tal método, discutido na metodologia, mostrou-se muito eficiente por permitir uma avaliação dinâmica da análise proposta perante modificações em quaisquer parâmetros existentes. Por fim, o método e os critérios foram finalmente aplicados em dois estudos de caso, selecionados com base em casos reais vivenciados pela indústria automotiva no desenvolvimento de dois projetos: um veículo hatch popular e um veículo sedan médio de luxo, ambos destinados a mercados emergentes. Através do estudo de caso, foi possível confrontar soluções de arquiteturas adotadas no passado, no presente e para um futuro próximo, além de confrontar também soluções adotadas para mercados desenvolvidos e para mercados emergentes. O resultado deste estudo comprovou a necessidade da existência de critérios específicos para mercados emergentes, a coerência destes critérios e a robustez do modelo apresentado. Convém ressaltar que, para o tema em questão (ou estudos de caso), a robustez e consistência do modelo de avaliação obtido e a importância comprovada dos critérios selecionados são pertinentes e válidos, considerando-se o fato de que a definição dos pesos e notas atribuídas ao modelo serem feitas pelo avaliador, nas quais são diretamente dependentes do conhecimento adquirido pela empresa (seja ela montadora ou fornecedora) e vivência do responsável pela avaliação, sujeitando-as, desta forma, a seus próprios conceitos. / The aim of this study is to establish the criteria of election of an electrical architecture tailor-made for the emergent markets, considering the necessities of market, legislation, innovations and/or new functions to be applied during the whole vehicles life-cycle. Due to this, the result of the bibliographical research of this study, defines the meaning of electrical architecture, and shows its evolution since the beginning of the automotive industry up to now, also presenting the main electrical systems available today, making clear the huge importance of the embedded electronics for the evolution of the automobile. This study also presents the technological trends and a brief description of techniques, criteria and development methodology for electrical architecture projects available today in the industry. Here after, the study defines the concepts of emergent market and developed market, showing their characteristics, market share and production volumes (historical and forecast), showing the importance of the emergent markets for the world-wide automotive industry nowadays and the needs for development of specific strategies for these markets. Based on the bibliographical research, documentary analysis and the unstructured interviews with active members of the automotive industry, the criteria for election of electrical architectures for emergent markets was established, as well as their describers and swing-weights. The definition of weights and describers is necessary for the use of the additive aggregation method a decision taking method which has the capacity to evaluate several alternatives simultaneously, through qualitative parameters. Such method, presented in the methodology chapter, was very efficient for dynamic evaluation of the proposals even before changes in its parameters. Finally, the method and the criteria were finally applied in two studies of case, based on real cases of automotive industry when developing two projects: a low-cost hatch vehicle and a mid-size luxury sedan vehicle, both designed for emergent markets. By the study of cases, it was possible to compare solutions of architectures adopted in the past, in the present and for a near future, and also to compare solutions adopted for developed markets and emergent markets. The results of this study proved the necessity of specific criteria for emergent markets, the coherence of the established criteria and the robustness of the adopted model. Regarding the studies of cases, the robustness and consistency of the evaluation model and the proved importance of the criteria are relevant and valid, even considering that the definition of the weights values and grades are always made by the evaluators. It means that they directly depend on the companys know-how and best practices (from carmakers or suppliers) and the professional experience of the evaluator, resulting, someway, in their own values for different companies.
220

Desenvolvimento de uma metodologia de simulação aplicada ao sistema de arrefecimento veicular. / Simulation metodology development applied to the vehicle cooling system.

Nelson Quim 17 May 2007 (has links)
Este trabalho visa o estudo de uma metodologia de simulação numérica aplicada ao processo de troca térmica do motor de um veículo de passeio. O processo de troca térmica é essencial para evitar o superaquecimento do motor, que provoca o rompimento do filme de óleo lubrificante dos pistões e, conseqüentemente, o seu travamento. Essa metodologia será útil nos estudos preliminares do sistema de arrefecimento de um veículo na fase inicial de projeto por meio de simulações virtuais, o que possibilitará a redução de protótipos, além de proporcionar um ganho em tempo de resposta. A metodologia utiliza um programa comercial de CFD para a simulação do processo de troca térmica no interior do compartimento do motor do veículo. As simulações foram realizadas com base nos testes físicos em túnel de vento que fazem parte do desenvolvimento e projeto de automóveis em condições de operação que representam situações críticas integrantes da vida operacional. Essas condições operacionais de teste, tais como a velocidade do veículo, as cargas térmicas, a potência dos ventiladores e outros parâmetros foram utilizadas como condições de contorno na validação do modelo do veículo. O processo de validação de modelos é composto por: validações de itens isolados do sistema de arrefecimento, avaliação do efeito da densidade de malha computacional de um modelo completo na vazão de ar nos trocadores de calor e simplificações no modelo para a redução do tempo de processamento. Neste trabalho três modelos distintos de veículos foram utilizados, sendo que dois deles para a validação na comparação com os resultados de túnel vento, enquanto o terceiro modelo foi utilizado para a validação da metodologia através de comparações com os dados obtidos nos testes em pista circular. Os resultados das simulações mostraram variações máximas de 5,5% na temperatura do líquido de arrefecimento na entrada do radiador em relação aos testes. A metodologia de simulação mostrou ser uma poderosa ferramenta de otimização durante a fase de desenvolvimento do projeto e complementando os testes físicos para o sistema de arrefecimento veicular. / The present work is applied to a development of a numerical simulation methodology for a passenger vehicle engine cooling process. The heat exchange process is essential to avoid the engine overheat which may result in the piston oil film separation and consequently its halt. This methodology will be useful for the preliminary studies of the cooling system at the initial phase through the virtual simulations which can reduce the number of prototypes and save proposals\' time response. The methodology uses commercial CFD software for airflow simulation and the thermal process at under hood. The simulations were based on the physical wind tunnel tests that are part of the automotive development, with operational conditions representing critical situations experienced by a vehicle in its operating life. The test conditions, such as vehicle speed, thermal loads, fan power and other parameters were used as the boundary conditions for the model validation. The validation process is based on the following phases: validation of the isolated cooling system components, the effect of mesh density at cooling airflow using a complete vehicle model and model simplification in order to improve the processing time. In this work development, three different models were used; two of them for validation with test tunnel data and the third, was used for methodology validation through the circular road test. The simulation results for tunnel and circular road showed 5.5% of differences for the radiator coolant inlet temperature when compared with physical tests. The methodology of the simulation is a powerful tool for optimization during the development phase and complementing the physical tests for the vehicle cooling systems.

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